Vibrating bar type musical instrument having strikers



Feb. 14, 1961 1 KENT ET AL 2,971,424

VIBRATING BAR TYPE MUSICAL INSTRUMENT HAVING STRIKERS Filed Jan. 10,1958 2 Sheets-Sheet 1 l l 26 I e o 75 57 G 17 l, 56 58 l i 79 G I l 78`l 1 INVENTORS Larry 111.2111 BY Thomas W. Norum AT TORN Y `4144141961L. KENT Em 2,971,424

VIBRATING BAR TYPE MUSICAL INSTRUMENT HAVING STRIKERS Filed Jan. 10,1958 2 Sheets-Sheet 2 INVENTORS Lorry Kent Thomas W. Norum FIGA UnitedStates Patent() VIBRATING BAR TYPE MUSICAL INSTRUMENT HAVING STRIKERSLarry Kent, 15 Center St., Mount Vernon, N.Y., and Thomas W. Norum, 1418Parker St., Bronx 62, N.Y.

Filed Jan. 10, 1958, Ser. No. 708,124

7 Claims. (Cl. 84-404) This invention relates to musical instruments ofthe type formed essentially by a series of bars having frequencies of amusical scale, means for striking the bars to institute vibration, andresonators coupled to the bars to improve the sound output of theinstrument. More particularly, the invention relates to instruments ofthis type having, in addition to the elements mentioned, rotatingclosure plates, or air beating fan blades as they are sometimes called,associated with the resonators and serving to produce rhythmicpulsations giving a pleasing vibrato effect. i

The vibraharp is an instrument of the type to which the inventionparticularly relates and which is highly popular when included among theinstruments of a small social dance orchestra. One of us has found,however, that it is diliicult, and indeed possibly inad* visable, toinclude a vibraharp among the pieces of a small social dance band asmusicians skilled in playing this instrument are few, and hence thepossibility of `replacement of a vibraharp musician, when this becomesnecessary, is uncertain. We have found, surprisingly,

that a celesta, modified to include rotating closure plates for theresonators, can advantageously be used in place of a vibraharp by asmall orchestra' provided that certain precautions are observed inrespect to the manner in which the closure plates are installed. Theseprecautions are set forth in detail hereinafter.

The celesta is formed essentially by a series of bars, means forstriking the bars and resonators coupled to the bars. It ischaracterized in that the striking means are individual hammers mountedover the bars and linked to keys of a keyboard. Hence, the celesta canbe played by any musician skilled in playing the piano, and thereforemusicians able to play the instrument are readily available. A furtheradvantage of a celesta is its cornpactness. The sound producing elementsare arranged in overlying tier-s so that no single dimension is so largeas to make the instrument cumbersome. For example, the instrument is ofsuch size and weight that it can be conveniently handled by two men, andcan be transported in a station wagon.

The celesta as such is a symphonic instrument adapted to produce upperregister notes. The quality of the sound produced is ethereal, and henceit is well suited to depict fairy dances. Thus, it was used. byTschaikovsky to depict the dance of the Sugarplums in 'his NutcrackerSuite. The fundamental frequency range of the instrument is fouroctaves, from C4 to C8. The modied celesta of the invention .produces asound significantly different from that of the celesta. The soundsimulates lCC that of vibraharp though it is of somewhat higher pitchthan the vibraharp. lf desired, the fundamental frequency range of themodified celesta can be changed so that the lowest note is in the rangeof C4 to F3 and thereby the sound of a vibraharp can be more closelysimulated.

The invention will now be described with reference to the accompanyingdrawings wherein an embodiment of the invention is set forth. In thedrawings:

Fig. l is a front elevation view of a modified celesta according to theinvention, the front cover having been removed so that the elements ofthe instrument can be seen;

Fig. 2 is an enlarged cross-section taken along line 2-2 of Fig. 1;

Fig. 3 is a cross-section taken along line 3- 3 in Fig. 2 with theclosure plate rotated 90 from the positions shown in Fig. 2;

Fig. 4 is an exploded perspective view of a resonator chamber includedin the instrument shown in Fig. l;

Fig. 5 is a cross-sectional view taken along line 5-5 or line 5-5 inFig. 4; and

Fig. 6 is an enlargement view taken along line 6-6 in Fig. l andrepresenting schematically the linkage between the hammers and keys ofthe keyboard.

Referring to the drawings, the instrument of the invention includes anouter case 8 having sidewalls 9 and 10 and back wall 11. Within theouter case 8, there are disposed three tiers 14, and 16 of sets ofsounding elements, each set including a bar 17, adapted to produce anote of a musical scale, a hammer 18 for striking the bar, and resonatorchamber 19 for improving the sound output of the bar. The hammers 18 areoperatively connected with manually operable keys 21 of keyboard 22 andthe instrument is played by manipulation of the keys in a mannergenerally similar to that in which a piano is played. The instrumentcovers four ocatves from C4 to C8 and the sounding elements are arrangedwithin the case so that the elements for producing each note areapproximately aligned with the key on the keyboard for the note.

In each tier of sounding elements, the resonator chamber 19 is disposedadjacent the bars 17 and is closely spaced therefrom with the upper wall23 (Fig. 4) of the resonator chamber confronting the bars. The bars aremounted for transverse vibration on cords 26 which extend longitudinallyover the resonator chamber and are supported above the resonator chamberby blocks 27 positioned at spaced intervals along the upper wall 23 ofthe chamber. The bars are loosely held in place by screws 2S whichextend through holes 29 disposed adjacent the ends of the bars and arethreaded into the upper wall 23 of the resonator chamber. Sleeves 30formed of resilient material are disposed in the holes 29 and serve toisolate the bars from the screws.

Each'resonator chamber includes a tapered section 33 in which there arebottomed holes 34 (Fig. 4) extending downward from chamber upper wall 23and serving as resonators for high notes, a middle hollow rectangularlsection 35 provided with transverse partitions 36 serving to divide thesection into resonator boxes 37 which serve as resonators for theintermediate notes, and an end hollow rectangular section 40 providedwithk transverse partitions 41 serving to divide the end section intoresonator boxes 42 which serve as resonators for the low notes. Eachresonator box 37 is provided with an opening 43 which extends throughthe upper wall 23 of the resonator chamber, and each resonator box 42 issimilarly provided with an opening 44 which likewise extends through theupper wall 23. Each of the openings 43 and 44 is spaced from each nextadjacent openings as can be seen in Fig. 4, and as can be seen in Fig.2, is aligned with a bar 17 so that suitable coupling between bars andresonator boxes is obtained.

The hammers 18 provided for striking the bars 17 are each mounted on alever arm 46 (Fig. 6) which is pivoted lon pivot rod 47 and mechanicallylinked at its input end 48 with key 21 by connecting rod 49. In a mannerwell known in the art key 21 is pivotally mounted as is indicated at 51and thus the hammer 18 can be actuated causing it to strike the bar 17by manipulation of the key. Cross bar 52 serves as a frame for theinstrument front cover (not shown) and top plate 53 together with itsdepending portion -54 serve to protect the linkage elements.

According to the invention, openings to the resonator chamber areprovided with closure plates 56 and means are provided for continuouslyrotating the closure plates so that the openings are alternativelyopened and closed and the desired sound effect is produced. As is shownin the drawings, closure plates 56 for each tier of sounding elementsare tixedly secured by set screws 57 (Fig. 3) at spaced intervals alonga rotatable shaft 58 which extends longitudinally of the resonatorchamber with the portions 60 of the shaft intermediate next adjacentclosure plates positioned in grooves 61 disposed in the upper wall 23 ofthe chamber and extending from each opening to the next adjacentopening. A pulley 59 for driving the shaft is mounted on one end thereofand bearings 62a are disposed at spaced intervals therealong and at theend thereofpopposite the pulley end. Bearing journal boxes formed byupper bearing caps 62 and lower bearing caps 63 fit into recesses 64disposed at appropriate positions along the upper wall 23. Screws 67serve to secure the journal boxes in place.

The pulleys 59 of the shafts 58 of the various tiers are interconnectedby drive belts 68 and an electric motor 69 is connected by belt y70 withone of the drive shafts 58 and serves to rotate the shafts and hence theclosure plates. A suitable rotation rate forthe closure plates is about180 r.p.m. and advantageously this rate is selectively variable between150 and 20() rpm. The motor 69 is energized from power lines 71 providedwith switch 72. A feature of the instrument of the invention is that itcan be played with the switch open, in which case it operates as acelesta, or with the switch closed, in which case the desired vibratoeffect is realized.

The size of the openings to the resonator boxes 36 and 42 of eachresonance chamber advantageously increases 'as the lower end of thescale is approached and since itr (Fig. 3) of closure plates 56 isparallel to the axis of rotation of the plates. This permits moreclosely positioning n thebars 17 to the resonance chamber than would bepossible if the closure plates were circular.

Thus, as can be seen in Fig. 2, notwithstanding proximatepositioning ofthe bars 17 and closure plates for openings 44, the closure plates clearthe bars during rotation.

- `We have discovered that in order toobtain satisfactory y soundproduction from resonator boxes provided with closure plates having`axially parallel peripheral portions 75, it is necessary that theperiphery`77 of each resonator box'opening 44 conform tothe peripheryofthe closure plate positionedrthereimras can be blest seen in Fig.Brand also that the periphery 77 of` each of theopenings be closelyspaced from its closure plate when Vthe closure plateV is in the closedposition. A clearance between closure plate and opening of not more thanabout 1,46 is satisfactory. We have also discovered that in order toobtain satisfactory sound production it is necessary to close thegrooves 61 intermediate each next adjacent opening to resonator boxes 37and 42. Appropriately, the grooves are closed by placing covers 78thereover and securing them in place with brads 79. Advantageously, thecovers 78 extend the entire length of the grooves. If desired, thepassageways for the shafts 5S intermediate resonator box openings can bemade by drilling a hole through the upper wall 23 of the resonatorchamber between next adjacent openings. This may not be convenienthowever, and we have found that the use of covers 7S as indicated in thedrawings is satisfactory.

Having new described our invention, what is claimed is:

l. A musical instrument comprising bars mounted for transversevibration, a hammer mounted adjacent each of said bars, and a manuallyoperable key operatively connected with each said hammer whereby saidbars can be struck with the hammers by actuating the keys, a resonatorchamber disposed adjacent said bars closely spaced there from with awall thereof confronting said bars, transverse partitions disposed insaid chamber providing a resonator box for each bar, means defining anopening in said wall to each said resonator box, each said opening beingspaced from the next adjacent openings and aligned with the bar of itsresonator box, a shaft which is mounted for rotation and extendslongitudinally of the resonator chamber and across the openings, aclosure plate disposed in each said opening, the closure plates beingmounted in spaced relationship on said shaft, each said closure platehaving a portion of the periphery thereof on each side of its axis ofrotation parallel to said axis, the periphery of each vopeningconforming to the periphery of its closure plate and being closelyspaced therefrom when its closure plate is in the closed position, meansdefining a groove in said walll extending frcm each opening to a nextadjacent opening each said groove being adapted to receive and havingpositioned therein the portion of said shaft intermediate the closureplates positioned in the openings joined by the groove, a cover plateover each said groove, and means for continuously rotating said closureplates whereby each said opening is alternatively open and closed.

2. A musical instrument according to claim l and including a lever armfor each of the hammers, the hammer of each lever arm being mounted onone end of the arm, and mechanical linkage means operativelyinterconnecting each lever arm with one of the keys.

3. A musical instrument comprising bars mounted for transversevibration, a resonator chamber spaced from said bars having a wallthereof confronting said bars, transverse partitions disposed in saidchamber providing a resonator box for each bar, means defining anopening in said wall te each said resonator box, each said opening ybeing spaced from each next vadjacent opening and aligned with the barof its resonator box, a shaft which is mounted for rotation and extendslongitudinally of the resonator chamber and across the openings, aclosure plate disposed in each said opening, the closure plates beingmounted in spaced relationship on said shaft, means defining a groove insaid wall extending from each opening to a next adjacent opening eachsaid groove being adapted to receive and having positioned therein theportion of the shaft intermediate the closure plates positioned in theopenings joined by the groove, a cover plate over each said groove,means for continuously rotating said closure plates, whereby each saidopening is alternatively open and closed.

4. A musical instrument according to claim 3, the cover the periphery ofeach opening conforming to the periph?l ery of its closure plate andbeing closely spaced therefrom when its closure plate is in the closedposition.

6. A musical instrument according to claim 3, including a hammer foreach of said bars and a manually operable key operatively connected witheach said hammer whereby said bars can be struck with the hammers byactuating the keys.

7. A musical instrument according to claim 6 and including a lever armfor each of the hammers, the hammer of each lever arm being mounted onone end of the arm, and mechanical linkage means operativelyinterconnecting each lever arm with one of the keys.

References Cited in the le of this patent UNITED STATES PATENTS KohlerFeb. 26, 1924 Greanleaf Nov. 14, 1933 OConnell et al Apr. 6, 1943 DargisDec. 19, 1950 FOREIGN PATENTS Great Britain Nov. 19, 1958

